Update graph data from subVI (while loop) that is also updated from outside the while loop

hello,

My graph gets updated just fine when it is not inside the while loop, infact inside the while loop is the same subvi that updates the graph outside the while. In the subvi that does not update the graph no data is getting passed at all. Its really mind boggling. I've tried a lot of things and can't seem to figure it out, so any help is appreciated.